Render author using a view mode specific template

modules/thunder_article/modules/thunder_fia/config/install/core.entity_view_mode.user.facebook_instant_articles_rss.yml

@@ -0,0 +1,9 @@
+langcode: en
+status: true
+dependencies:
+  module:
+    - user
+id: user.facebook_instant_articles_rss
+label: 'Facebook Instant Articles: RSS'
+targetEntityType: user
+cache: true

modules/thunder_article/modules/thunder_fia/templates/user--facebook-instant-articles-rss.html.twig

@@ -0,0 +1 @@
+<a>{{ user.displayName }}</a>

modules/thunder_article/modules/thunder_fia/thunder_fia.install

@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * @file
+ * Install, update and uninstall functions for the thunder_fia module.
+ */
+
+/**
+ * Add FIA view mode for users.
+ */
+function thunder_fia_update_8001() {
+  \Drupal::service('module_installer')->install([
+    'config_update',
+  ]);
+
+  /** @var Drupal\config_update\ConfigRevertInterface $configReverter */
+  $configUpdate = \Drupal::service('config_update.config_update');
+
+  if (empty($configUpdate->getFromActive('entity_view_mode', 'user.facebook_instant_articles_rss'))) {
+    $configUpdate->import('entity_view_mode', 'user.facebook_instant_articles_rss');
+  }
+
+}

modules/thunder_article/modules/thunder_fia/thunder_fia.module

@@ -58,14 +58,8 @@ function thunder_fia_preprocess_views_view_row_fia(&$variables) {
       }
     }
 
-    // Change author name to "firstname lastname".
-    $owner = $node->getOwner();
-    if (isset($owner->first_name, $owner->last_name)) {
-      $name = $owner->first_name->value . ' ' . $owner->last_name->value;
-      if ($name = trim($name) && !empty($variables['options']['author'])) {
-        $variables['options']['author'] = ['#markup' => '<a>' . $name . '</a>'];
-      }
-    }
+    $render_controller = \Drupal::entityTypeManager()->getViewBuilder($node->getOwner()->getEntityTypeId());
+    $variables['options']['author'] = $render_controller->view($node->getOwner(), 'facebook_instant_articles_rss', NULL);
   }
 }